PERC-UPC - Power Electronics Research Centre
Total activity: 3757
Type
Research group
Type of group
Specific research center
Acronym
PERC
Address
ETSEIB. Edifici H. Despatx 9-24. Av. Diagonal, 647 Open in new window
City
Barcelona
URL
http://held.perc.upc.edu/?set_language=es Open in new window
Keywords
PERC-UPC - Centre de Recerca d'Electrònica de Potència UPC

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1 to 50 of 3757 results
  • Analysis and design of fault tolerant axial flux permanent magnet synchronous motors

     Saavedra Ordoñez, Harold
    Universitat Politècnica de Catalunya
    Theses

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    Debido a las nuevas políticas de conservación medio ambiental, los vehículos eléctricos toman una posición más importante en la sociedad actual. Los motores eléctricos constituyen el corazón de la cadena de tracción de un EV, por esta razón se debe encaminar la investigación hacia el diseño de motores de mayor eficiencia y fiabilidad. Este trabajo se enfoca en el análisis y diseño óptimo de un motor de flujo axial con tolerancia a fallos. Como base, se parte de la investigación de los procedimientos analíticos de diseño de motores eléctricos y del estudio de los efectos de los fallos eléctricos en elcomportamiento de estos, de acuerdo a la configuración específica de cada máquina. Para desarrollar esta tesis se hará uso de herramientas analíticas y de métodos de simulación basados en métodos finitos (FEM). En primera parte se hace un estudio del estado del arte del diseño de motores eléctricos tolerantes a fallos, en el cual se identifican las posibles configuraciones a usar y las principales reglas de diseño de estos motores. Debido a que las consecuencias de un cortocircuito entre espiras pueden ser catastróficas para el motor de imanes permanentes, en el siguiente capítulo se analiza su efecto en dependencia de la configuración de los devanados del motor, además de su posible detección. Ladetección del cortocircuito se basa en el análisis del espectro de frecuencias de las corrientes del estator y la componente homopolar de voltaje (ZSVC). Para este estudio se seleccionan los 5 tipos de bobinados generalmente usados en motores eléctricos. Tomando en cuenta las tendencias de sistemas tolerantes a fallos de utilizar la redundancia de elementos, el estudio del cortocircuito se extiende al motor de 5 fases, para esto se desarrolla un modelo paramétrico del motor, el cual es utilizado para seleccionar los armónicos de frecuencias que permitan la detección del cortocircuito entre espiras en su fase más temprana. De la misma manera estos armónicos son analizados en modelos de simulación por elementosfinitos, probando su potencial para el desarrollo de algoritmo de detección de fallos, característica deseable en los sistemas tolerantes a fallos. En última parte de este capítulo se estudia el efecto de la desmagnetización en el comportamiento de motores, en particular la influencia de la forma de los imanes cuando el motor funciona en régimen de fallo, como conclusión de este estudio se selecciona la forma de imán que mejor se comporta ante este tipo de fallos. Una vez analizado los posibles fallos eléctricos en el motor, el trabajo se centra en el diseño electromagnético óptimo de una máquina de flujo axial. El diseño optimo se apoya en el uso de ecuaciones analíticas del motor (AFPMM) y se valida por medio de simulaciones FEM. Para lograr el diseño óptimo de hace uso de algoritmo de optimización heurísticos, enparticular los algoritmos genéticos. A estos algoritmos se les aplica las restricciones anteriormente encontradas en los estudios de fallos y en el estado de arte de motores tolerantes a fallos. Finalmente aplicando una serie de ecuaciones analíticas y teniendo en cuenta las restricciones de un diseño tolerante a fallos previamente seleccionadas se obtiene el diseño electromagnético óptimo de un motor de flujo axial tolerante a fallos. Para el proceso de optimización se utilizan algoritmos genéticos multi-objetivos en donde se busca maximizar la densidad de potencia y la eficiencia. Por último, el modelo del motor pentafásico de flujo axial es verificado por medio de simulaciones en elementos finitos.

  • RTC-2014-3089-3-Anualitat 2015

     Romeral Martinez, Jose Luis
    Competitive project

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  • Observer-based open transistor fault diagnosis and fault-tolerant control of five-phase permanent magnet motor drive for application in electric vehicles

     Salehifar, Mehdi; Salehi Arashloo Arashloo, Ramin; Moreno Eguilaz, Juan Manuel; Sala Caselles, Vicente Miguel; Romeral Martinez, Jose Luis
    IET power electronics
    Vol. 8, num. 1, p. 76-87
    DOI: 10.1049/iet-pel.2013.0949
    Date of publication: 2015-01-01
    Journal article

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    To meet increasing demand for higher reliability in power electronics converters applicable in electric vehicles, fault detection (FD) is an important part of the control algorithm. In this study, a model-based open transistor fault diagnsosis method is presented for a voltage-source inverter (VSI) supplying a five-phase permanent magnet motor drive. To realise this goal, a model-based observer is designed to estimate model parameters. After that, the estimated parameters are used to design a sliding mode observer in order to estimate the phase current in an ideal model. Subsequently, the proposed FD technique measures the similarity between the estimated current and real current using cross-correlation factor. This factor is used for the first time in this study to define a FD index in VSI. The presented FD scheme is simple and fast; also, it is able to detect multiple open switch or open phase faults in contrast to conventional methods. On the other side, in order to track reference current of the motor, the estimated parameters are used to design a proportional resonant controller. The FD technique is used to operate a multiphase fault-tolerant brushless direct current (BLDC) motor drive. Experimental results on a five-phase BLDC motor with in-wheel outer rotor applicable in electrical vehicles are conducted to validate the theory.

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    FPGA based robust open transistor fault diagnosis and fault tolerant sliding mode control of a five-phase PM motor drive  Open access

     Salehifar, Mehdi; Salehi Arashloo Arashloo, Ramin; Moreno Eguilaz, Juan Manuel; Sala Caselles, Vicente Miguel
    Journal of Power Electronics
    Vol. 15, num. 1, p. 131-145
    DOI: 10.6113/JPE.2015.15.1.131
    Date of publication: 2015-01
    Journal article

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    The voltage-source inverters (VSI) supplying a motor drive are prone to open transistor faults. To address this issue in faulttolerant drives applicable to electric vehicles, a new open transistor fault diagnosis (FD) method is presented in this paper. According to the proposed method, in order to define the FD index, the phase angle of the converter output current is estimated by a simple trigonometric function. The proposed FD method is adaptable, simple, capable of detecting multiple open switch faults and robust to load operational variations. Keeping the FD in mind as a mandatory part of the fault tolerant control algorithm, the FD block is applied to a five-phase converter supplying a multiphase fault-tolerant PM motor drive with nonsinusoidal unbalanced current waveforms. To investigate the performance of the FD technique, the fault-tolerant sliding mode control (SMC) of a five-phase brushless direct current (BLDC) motor is developed in this paper with the embedded FD block. Once the theory is explained, experimental waveforms are obtained from a five-phase BLDC motor to show the effectiveness of the proposed FD method. The FD algorithm is implemented on a field programmable gate array (FPGA).

  • Configuración de los parámetros del sistema de detección de obstáculos del guanay II  Open access

     Galarza, Cesar; Masmitja Rusiñol, Ivan; Gonzalez Agudelo, Julian; Prat Tasias, Jordi; Gomariz Castro, Spartacus
    Instrumentation viewpoint (electrònic)
    num. 17, p. 19-20
    Date of publication: 2014-12-15
    Journal article

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    En el presente trabajo se muestran los avances realizados en el sistema de detección de obstáculos del AUV Guanay II y la configuración óptima del sistema. In this work are presented the advances of the obstacle detection system of Guanay II AUV and the optimal configuration of this.

  • System designed for the acquisition of volcanic seismicity  Open access

     Carreras Pons, Normandino; Gomariz Castro, Spartacus; Manuel Lazaro, Antonio
    Instrumentation viewpoint (electrònic)
    num. 17, p. 22-23
    Date of publication: 2014-12-15
    Journal article

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    This work presents a system created for the acquisition of volcanic seismicity. In order to prevent the danger of a volcanic eruption, volcanoes are monitored to determine the state on which they are. One of these parameters is the seismicity generated by the movement of ground. To monitoring this parameter, it is been created a low cost and low power system mounted in a waterproof case to be installed in hard environments with adverse conditions. It is an autonomous system built to be used in longterm campaigns. This equipment incorporates a low power microprocessor as the core of the system, three acquisition channels and a GPS to synchronize the time base. Data can be stored in a SD memory or it can be sent remotely via radio-frequency. The final tests show a correct acquisition of the system with an event produced in the Canary Islands.

  • Disseny Òptim d'amplificadors d'audio commutats DCI-NPC d'alta potència i qualitat  Open access

     Sala Caselles, Vicente Miguel
    Department of Electronic Engineering, Universitat Politècnica de Catalunya
    Theses

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    L'amplificació en Classe-D ha suposat una millora absoluta en quant a eficiència elèctrica en els sistemes d'amplificació d'àudio, però ha estat durant la primera dècada d'estabilització d'aquesta tecnologia al mercat, quan els fabricants han fet pública la seva preocupació per la incompatibilitat entre aplicacions de so distribuït o PA (Public Addres) i so HiFi o Professional. Els sistemes d'alta qualitat de so, necessiten de freqüències de commutació (>1MHz) per les quals les pèrdues en commutació no permeten treballar a potències elevades (>250W). Per al contrari, per aplicacions d'amplificació de so de potència es necessita d'alta eficiència elèctrica, amb el que les freqüències de commutació han de quedar fixades a valors baixos (<400kHz), reduint la qualitat del senyal. Aquesta incompatibilitat d'aplicacions s'anomena Compromís Qualitat-Potència. Les topologies Multinivell de convertidors electrònics de potència DC-AC, per les seves característiques, permeten treballar a gran potència (augmentant la tensió de treball), mantenint o augmentant la qualitat del senyal de sortida mitjançant els nivells extra en el senyal PWM de sortida. L'aplicació d'aquestes topologies en el mon de l'Amplificació de So, podria suposar la resolució del compromís Qualitat-Potència, i per tant de la principal problemàtica que presenta la Classe-D. Aquesta Tesis proposa en primer lloc l'estudi de les topologies Multinivell per determinar quina és la que millors prestacions i viabilitat mostra en quant a la seva aplicació com a Amplificador d'Àudio Commutat. Un cop determinada la Topologia Òptima, es proposa estudiar, caracteritzar i modelar els fenòmens no ideals i mecanismes generadors d'errors de Temps i d'Amplitud al polsos del senyal PWM de sortida d'un Amplificador amb la Topologia seleccionada. A partir d'aquests models, s'estudia mitjançant simulació els efectes dels errors en els senyals de sortida, expressant aquests efectes mitjançant factors de mèrit no normatius. Aquests factors de mèrit, al contrari que els normatius, permeten avaluar quantitativa i qualitativament el grau d'afectació de cada una de les diferents fonts d'errors intrínseques al disseny i a la topologia. A partir d'aquests resultats es desenvolupen Models d'Estimació dels Factors de Mèrit No Normatius, que permeten calcular el valor d'Error d'Amplitud i Distorsió, local o total, generat per qualsevol font d'error de la Cadena d'Amplificació de So. Per tal d'expressar aquesta informació en valors normatius, es desenvolupen Models d'Estimació d'Eficiències Elèctriques, Distorsió (THD) i Eficiència de Senyal a partir dels valors estimats d'Error d'Amplitud i Distorsió no normatius. Aquests models d'estimació proveeixen d'una informació que, un cop ordenada i classificada per tal de ser utilitzada, com a eina en els diferents nivells del procés de disseny, producció i comercialització d'equips d'amplificació commutada, permet, de forma òptima en la fase de pre-disseny, la selecció de components i la presa de decisions per tal d'assegurar, un cop construït, la futura validació de l'amplificador commutat multinivell, sota criteris normatius de mercat. Els models d'estimació d'Errors d'Amplitud i Distorsió, així com els models d'estimació de les Eficiències Elèctriques, de Distorsió i de Senyal han estat validats mitjançant la seva comparació amb resultats experimentals obtinguts a partir d'un prototipus de laboratori i un prototipus de fabricació industrial, dissenyat per una empresa del sector a partir de l'ús de les Eines de Disseny Òptim basades en els Models d'Estimació, desenvolupades en aquesta Tesis. Els resultats experimentals confirmen que els valors normatius mesurats d'Eficiència Elèctrica, Distorsió i Eficiència de Senyal estan dintre dels valors acceptables per la comercialització de l'equip.

    Class-D Amplification has been an absolute improvement in terms of electrical efficiency in audio amplification systems, but it has been during the first stabilization decade of this technology in the market when manufacturers have made public their concern about the incompatibility between distributed audio or PA (Public Address) applications and HiFi or Professional sound applications. High quality sound systems need switching frequencies (>1MHz) whose switching losses do not allow to work at high power (>250W). To the contrary, applications for high power amplification need high electrical efficiency, so the switching frequencies must be set to low values (<400kHz), reducing the signal quality. This incompatibility is called Power-Quality Compromise. The Characteristics of the Multilevel Topologies of DC-AC power electronic converters allow them to work at high power (increasing the working voltage) while maintaining or even increasing the quality of the output signal using the extra levels in the PWM output signal. The application of these topologies in the world of sound amplification could lead to the resolution of the Quality-Power Compromise and so, the main problem of the Class-D amplifiers. In the first place, this Thesis proposes the study of the Multilevel Topologies in order to determine the one who shows better features and feasibility, in terms of implementation as a Switching Audio Amplifier. Having determined the Optimal Topology, it is proposed to study, characterize and model the non-ideal phenomena and those mechanisms who generate Time and Pulse Width errors in the PWM output signals of the Amplifier Topology selected. Using these models, the effects of the errors in the output signals are studied by means of computer simulation, expressing these effects using non normative merit factors. These merit factors, unlike regulations, allow to evaluate quantitatively and qualitatively the degree of involvement of each one of the different error sources intrinsic to the design and topology. From these results it can be developed Estimation Models of the Non Normative Merit Factors, which allow to calculate the values of the Width Error and Distortion, local or total, generated by any source of error in the Amplification Sound Chain. In order to express this information in normative values, Estimation Models of Electric Efficiency, Distortion (THD) and Signal Efficiency are developed from the estimated non normative values of Width Error Distortion. These estimation models provide an information that, once ordered and classified in order to be used as a tool in the different levels of the design process, production and marketing of Switching Amplifier Equipment, allow the optimal component selection in the pre-design phase and the decision-making process to ensure the future validation of the Multilevel Switching Amplifier under market regulatory criteria. The Estimation models of the Width and Distortion Errors and the estimation models of the Electrical Efficiency, Distortion and Signal have been validated through the comparison with experimental results from a laboratory prototype and an industrial manufacturing prototype, designed by a company in the sector using the Optimal Design Tools based on the Estimation Models developed in this Thesis. The experimental results confirm that the normative values measured of the Electrical Efficiency, Distortion and Signal Efficiency are within the acceptable values for the commercialization of the equipment.

    L'amplificació en Classe-D ha suposat una millora absoluta en quant a eficiència elèctrica en els sistemes d'amplificació d'àudio, però ha estat durant la primera dècada d'estabilització d'aquesta tecnologia al mercat, quan els fabricants han fet pública la seva preocupació per la incompatibilitat entre aplicacions de so distribuït o PA (Public Addres) i so HiFi o Professional. Els sistemes d'alta qualitat de so, necessiten de freqüències de commutació (>1MHz) per les quals les pèrdues en commutació no permeten treballar a potències elevades (>250W). Per al contrari, per aplicacions d'amplificació de so de potència es necessita d'alta eficiència elèctrica, amb el que les freqüències de commutació han de quedar fixades a valors baixos (<400kHz), reduint la qualitat del senyal. Aquesta incompatibilitat d'aplicacions s'anomena Compromís Qualitat-Potència. Les topologies Multinivell de convertidors electrònics de potència DC-AC, per les seves característiques, permeten treballar a gran potència (augmentant la tensió de treball), mantenint o augmentant la qualitat del senyal de sortida mitjançant els nivells extra en el senyal PWM de sortida. L'aplicació d'aquestes topologies en el mon de l'Amplificació de So, podria suposar la resolució del compromís Qualitat-Potència, i per tant de la principal problemàtica que presenta la Classe-D. Aquesta Tesis proposa en primer lloc l'estudi de les topologies Multinivell per determinar quina és la que millors prestacions i viabilitat mostra en quant a la seva aplicació com a Amplificador d'Àudio Commutat. Un cop determinada la Topologia Òptima, es proposa estudiar, caracteritzar i modelar els fenòmens no ideals i mecanismes generadors d'errors de Temps i d'Amplitud al polsos del senyal PWM de sortida d'un Amplificador amb la Topologia seleccionada. A partir d'aquests models, s'estudia mitjançant simulació els efectes dels errors en els senyals de sortida, expressant aquests efectes mitjançant factors de mèrit no normatius. Aquests factors de mèrit, al contrari que els normatius, permeten avaluar quantitativa i qualitativament el grau d'afectació de cada una de les diferents fonts d'errors intrínseques al disseny i a la topologia. A partir d'aquests resultats es desenvolupen Models d'Estimació dels Factors de Mèrit No Normatius, que permeten calcular el valor d'Error d'Amplitud i Distorsió, local o total, generat per qualsevol font d'error de la Cadena d'Amplificació de So. Per tal d'expressar aquesta informació en valors normatius, es desenvolupen Models d'Estimació d'Eficiències Elèctriques, Distorsió (THD) i Eficiència de Senyal a partir dels valors estimats d'Error d'Amplitud i Distorsió no normatius. Aquests models d'estimació proveeixen d'una informació que, un cop ordenada i classificada per tal de ser utilitzada, com a eina en els diferents nivells del procés de disseny, producció i comercialització d'equips d'amplificació commutada, permet, de forma òptima en la fase de pre-disseny, la selecció de components i la presa de decisions per tal d'assegurar, un cop construït, la futura validació de l'amplificador commutat multinivell, sota criteris normatius de mercat. Els models d'estimació d'Errors d'Amplitud i Distorsió, així com els models d'estimació de les Eficiències Elèctriques, de Distorsió i de Senyal han estat validats mitjançant la seva comparació amb resultats experimentals obtinguts a partir d'un prototipus de laboratori i un prototipus de fabricació industrial, dissenyat per una empresa del sector a partir de l'ús de les Eines de Disseny Òptim basades en els Models d'Estimació, desenvolupades en aquesta Tesis. Els resultats experimentals confirmen que els valors normatius mesurats d'Eficiència Elèctrica, Distorsió i Eficiència de Senyal estan dintre dels valors acceptables per la comercialització de l'equip.

  • Mixed resistive unbalance and winding inter-turn faults model of permanent magnet synchronous motors

     Urresty Betancourt, Julio; Riba Ruiz, Jordi Roger; Romeral Martinez, Jose Luis; Ortega Redondo, Juan Antonio
    Electrical engineering
    Vol. 96, num. 4, p. 1-11
    DOI: 10.1007/s00202-014-0316-z
    Date of publication: 2014-12-11
    Journal article

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  • Agustín de Betancourt y Molina

     Busquets Monge, Sergio
    Award or recognition

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  • Dynamic average modeling of a bidirectional solid state transformer for feasibility studies and real-time implementation

     Martinez Velasco, Juan Antonio; Alepuz Menendez, Salvador; Gonzalez Molina, Francisco; Martin Arnedo, Jacinto
    Electric power systems research
    Vol. 117, p. 143-153
    DOI: 10.1016/j.epsr.2014.08.005
    Date of publication: 2014-12-01
    Journal article

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    Detailed switching models of power electronics devices often lead to long computing times, limiting the size of the system to be simulated. This drawback is especially important when the goal is to implement the model in a real-time simulation platform. An alternative is to use dynamic average models (DAM) for analyzing the dynamic behavior of power electronic devices. This paper presents the development of a DAM for a bidirectional solid-state transformer and its implementation in a real-time simulation platform. Several case studies have been carried out in order to evaluate the behavior of the model under different operating conditions, check its feasibility for power quality improvements and explore the implementation in a real-time simulation platform. (C) 2014 Elsevier B.V. All rights reserved.

  • A three-phase frequency-adaptive phase-locked loop for independent single-phase operation

     Mirhosseini, Mitra; Pou Felix, Josep; Agelidis, Vassilios; Robles Sestafe, Eider; Ceballos Recio, Salvador
    IEEE transactions on power electronics
    Vol. 29, num. 12, p. 6255-6259
    DOI: 10.1109/TPEL.2014.2328657
    Date of publication: 2014-12-01
    Journal article

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    This letter proposes a phase-locked loop (PLL) able to operate as an independent single-phase PLL in the context of three-phase systems. Its key advantage is that the extracted information allows the independent control of both the active and reactive powers for each phase. The proposed PLL utilizes moving average filters and, hence, remains robust under unbalanced and highly distorted voltages. A frequency estimator is also presented and incorporated in the PLL angle detector path to make it frequency adaptive. The performance of the proposed PLL is verified experimentally and results for frequency change, phase-angle jump, and unbalanced voltage sag are reported as a confirmation of its potential. © 2014 IEEE.

  • Predictive control for low-voltage ride-through enhancement of three-level-boost and NPC-converter-based PMSG wind turbine

     Yaramasu, Venkata; Wu, Bin; Alepuz Menendez, Salvador; Kouro, Samir
    IEEE transactions on industrial electronics
    Vol. 61, num. 12, p. 6832-6843
    DOI: 10.1109/TIE.2014.2314060
    Date of publication: 2014-12-01
    Journal article

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    In this paper, a predictive control scheme is proposed for the low-voltage ride-through (LVRT) enhancement of direct-driven permanent-magnet-synchronous-generator-based megawatt-level wind turbines. The proposed method uses the turbine-generator rotor inertia to store the surplus energy during the grid voltage dips. The power conversion system is realized using a three-phase diode-bridge rectifier, a three-level-boost converter, and a neutral-point-clamped (NPC) inverter. The wind turbine requirements, such as maximum power point tracking, net dc-bus voltage control, balancing of the dc capacitor voltages, and reactive power generation, are modeled as the reference control variables. The generator-and grid-side cost functions are defined to deal with these control objectives. During each sampling interval, the control goals are achieved based on the minimization of cost functions. The coordination of boost and NPC converters and the exchange of reference control variables during normal and LVRT operation are formulated such that the power converters operate in a safe mode while meeting the grid code requirements. Simulation and experimental results are presented to validate the proposed strategy.

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    Detection of inter-turn faults in five-phase permanent magnet synchronous motors  Open access

     Saavedra Ordoñez, Harold; Riba Ruiz, Jordi Roger; Romeral Martinez, Jose Luis
    Advances in Electrical and Computer Engineering
    Vol. 14, num. 4
    DOI: 10.4316/AECE.2014.04008
    Date of publication: 2014-11-27
    Journal article

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    Five-phase permanent magnet synchronous motors (PMSMs) have inherent fault-tolerant capabilities. This paper analyzes the detection of inter-turn short circuit faults in five-phase PMSMs in their early stage, i.e. with only one turn in short circuit by means of the analysis of the stator currents and the zero-sequence voltage component (ZSVC) spectra. For this purpose, a parametric model of five-phase PMSMs which accounts for the effects of inter-turn short circuits is developed to determine the most suitable harmonic frequencies to be analyzed to detect such faults. The amplitudes of these fault harmonic are analyzed in detail by means of finite-elements method (FEM) simulations, which corroborate the predictions of the parametric model. A low-speed five-phase PMSM for in-wheel applications is studied and modeled. This paper shows that the ZSVC-based method provides better sensitivity to diagnose inter-turn faults in the analyzed low-speed application. Results presented under a wide speed range and different load levels show that it is feasible to diagnose such faults in their early stage, thus allowing applying a post-fault strategy to minimize their effects while ensuring a safe operation.

  • Predictive current control of outer-rotor five-phase BLDC generators applicable for off-shore wind power plants

     Romeral Martinez, Jose Luis; Salehi Arashloo Arashloo, Ramin; Salehifar, Mehdi; Moreno Eguilaz, Juan Manuel
    Electric power systems research
    DOI: 10.1016/j.epsr.2014.11.004
    Date of publication: 2014-11-26
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  • Review of micro- and small-scale technologies to produce electricity and heat from Mediterranean forests' woodchips

     Gonzalez Junca, Arnau; Riba Ruiz, Jordi Roger; Puig Vidal, Rita; Navarro, Pere
    Renewable and sustainable energy reviews
    Vol. 43, p. 143-155
    DOI: 10.1016/j.rser.2014.11.013
    Date of publication: 2014-11-22
    Journal article

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    In the current energy conjunction, with an expected growth of energy consumption in a context of fossil fuel depletion, more focus is being placed on renewable energy sources (RES) for electricity generation. One of the most appealing alternatives is biomass, which can be efficiently used to generate electricity as well as heat with the application of cogeneration technologies that enhance the efficiency of the entire energy conversion process. The Mediterranean basin is a region with a recognized potential for electricity and heat production using primary forest biomass and sub-products from sawmills, among which highlight wood chips for their easiness to be obtained, processed and dried as well as for their good and stable burning or gasification behavior. However, in order to efficiently use the available resources, that is, minimizing logistical requirements to reduce the energy necessary for the electricity generation process, the biomass found in Mediterranean forests can only be used at micro- and small-scale levels to be compatible with sustainable forestry practices. This article is aimed to describe the different technological alternatives to convert wood chips into electricity and heat and it also reviews and compares the current performances in terms of efficiency of these technologies at the micro- and small-scale levels.

  • Identificación de defectos en cables de media tensión aplicando métodos multivariables

     Riba Ruiz, Jordi Roger; Casals Torrens, Pablo; Bosch Tous, Ricardo
    Dyna
    Vol. 89, num. 6, p. 633-641
    DOI: 10.6036/7161
    Date of publication: 2014-11-13
    Journal article

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  • Reduction of Output Common Mode Voltage Using a Novel SVM Implementation in Matrix Converters for Improved Motor Lifetime

     Espina, Jordi; Ortega Garcia, Carlos; De Lilo, Liliana; Empringham, Lee; Balcells Sendra, Josep; Arias Pujol, Antoni
    IEEE transactions on industrial electronics
    Vol. 99, num. 11, p. 5903-5911
    DOI: 10.1109/TIE.2014.2304931
    Date of publication: 2014-11-01
    Journal article

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    This paper presents the study of an alternative space vector modulation (SVM) implementation for matrix converters (MCs), which reduces the output common mode (CM) voltage. The strategy is based on replacing the MC zero vectors with rotating ones. In doing this, the CM voltage (CMV) can be reduced, which, in turn, reduces the CM leakage current. By reducing the CM current, which flows inside the motor through the bearings and windings, the induction motor (IM) deterioration can be slowed down. This paper describes the SVM pattern and analyzes the CMV and the leakage current paths. Simulation and experimental results based on an MC-IM drive are provided to corroborate the presented approach.

    This paper presents the study of an alternative Space Vector Modulation (SVM) implementation for Matrix Converters (MC) which reduces the output Common Mode (CM) voltage. The strategy is based on replacing the MC zero vectors by the rotating ones. In doing this, the CM voltage can be reduced which in-turn reduces the CM leakage current. By reducing the CM current, which flows inside the motor through the bearings and windings, the Induction Motor (IM) deterioration can be slowed down. The paper describes the SVM pattern and analyses the CM voltage and the leakage current paths. Simulation and experimental results based on a MC-IM drive are provided to corroborate the presented approach.

  • Modeling and design of voltage support control schemes for three-phase inverters operating under unbalanced grid conditions

     Castilla Fernandez, Miguel; Miret Tomas, Jaume; Camacho Santiago, Antonio; Garcia de Vicuña Muñoz de la Nava, Jose Luis; Matas Alcala, Jose
    IEEE transactions on power electronics
    Vol. 29, num. 11, p. 6139-6150
    DOI: 10.1109/TPEL.2013.2296774
    Date of publication: 2014-11-01
    Journal article

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    Three-phase inverters equipped with voltage support control schemes have been successfully used to alleviate the negative impact of voltage imbalance on electric power systems. With these schemes, dc-link voltage ripple and current harmonics are significantly reduced by processing the positive and negative sequence components separately. However, the design methods for tuning the parameters of these control schemes have one or more of the following limitations: 1) the design is a very time-consuming task, 2) it is conservative, 3) it does not guarantee the specifications for all the considered situations, and 4) the system can be unstable in some abnormal conditions. As an alternative, this paper presents a design method based on the analysis of oscillations in nonlinear systems. The method proceeds by first developing simple and accurate models of the power system, second it reveals the system features through an in deep analysis of the derived models, and third it introduces a systematic design procedure for tuning the parameters of the control schemes. As an example, a voltage support control scheme for a three-phase inverter operating under an unbalanced voltage sag is designed and validated experimentally.

  • Access to the full text
    Reactive Power Control for Distributed Generation Power Plants to Comply With Voltage Limits During Grid Faults  Open access

     Camacho Santiago, Antonio; Castilla Fernandez, Miguel; Miret Tomas, Jaume; Guzman Sola, Ramon; Borrell Sanz, Angel
    IEEE transactions on power electronics
    Vol. PP, num. 11, p. 6224-6234
    DOI: 10.1109/TPEL.2014.2301463
    Date of publication: 2014-11-01
    Journal article

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    Grid faults are one of the most severe problems for network operation. Distributed generation power plants can help to mitigate the adverse effects of these perturbations by injecting the reactive power during the sag and the postfault operation. Thus, the risk of cascade disconnection and voltage collapse can be reduced. The proposed reactive power control is intended to regulate the maximum and minimum phase voltages at the point of common coupling within the limits established in grid codes for continuous operation. In balanced three-phase voltage sags, the control increases the voltage in each phase above the lower regulated limit by injecting the positive sequence reactive power. In unbalanced voltage sags, positive and negative sequence reactive powers are combined to flexibly raise and equalize the phase voltages; the maximum phase voltage is regulated below the upper limit and the minimum phase voltage just above the lower limit. The proposed control strategy is tested by considering a distant grid fault and a large grid impedance. Selected experimental results are reported in order to validate the behavior of the control scheme.

    Grid faults are one of the most severe problems for network operation. Distributed generation power plants can help to mitigate the adverse effects of these perturbations by injecting reactive power during the sag and the post-fault operation. Thus, the risk of cascade disconnection and voltage collapse can be reduced. The proposed reactive power control is intended to regulate the maximum and minimum phase voltages at the point of common coupling within the limits established in grid codes for continuous operation. In balanced three-phase voltage sags, the control increases the voltage in each phase above the lower regulated limit by injecting positive sequence reactive power. In unbalanced voltage sags, positive and negative sequence reactive powers are combined to flexibly raise and equalize the phase voltages; maximum phase voltage is regulated below the upper limit and the minimum phase voltage just above the lower limit. The proposed control strategy is tested by considering a distant grid fault and a large grid impedance. Selected experimental results are reported in order to validate the behavior of the control scheme.

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    A methodology to introduce sustainability into the Final Year Project to foster sustainable engineering projects  Open access

     Lopez Alvarez, David; Sanchez Carracedo, Fermin; Vidal Lopez, Eva Maria; Pegueroles Valles, Josep Rafel; Alier Forment, Marc; Cabre Garcia, Jose Maria; Garcia Almiñana, Jordi; García, Helena
    Annual Frontiers in Education Conference
    p. 2360-2366
    Presentation's date: 2014-10-24
    Presentation of work at congresses

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    The introduction of sustainability skills into higher education curricula is a natural effect of the increasing importance of sustainability in our daily lives. Topics like green computing, sustainable design or environmental engineering have become part of the knowledge required by today’s engineers. Furthermore, we strongly believe that the introduction of this skill will eventually enable future engineers to develop sustainable products, services and projects. The Final Year Project is the last academic stage facing students and a step towards their future professional engineering projects. As such, it constitutes a rehearsal for their professional future and an ideal opportunity for reflecting on whether their Final Year Project is sustainable or not, and to what extent. It also provides a good tool for reviewing the lessons learned about sustainability during the degree course and for applying them in a holistic and integrated way. In this paper, we present a guide that allows both students and advisors to think carefully about the sustainability of engineering projects, in particular the Final Year Project.

    The introduction of sustainability skills into higher education curricula is a natural effect of the increasing importance of sustainability in our daily lives. Topics like green computing, sustainable design or environmental engineering have become part of the knowledge required by today’s engineers. Furthermore, we strongly believe that the introduction of this skill will eventually enable future engineers to develop sustainable products, services and projects. The Final Year Project is the last academic stage facing students and a step towards their future professional engineering projects. As such, it constitutes a rehearsal for their professional future and an ideal opportunity for reflecting on whether their Final Year Project is sustainable or not, and to what extent. It also provides a good tool for reviewing the lessons learned about sustainability during the degree course and for applying them in a holistic and integrated way. In this paper, we present a guide that allows both students and advisors to think carefully about the sustainability of engineering projects, in particular the Final Year Project.

    Postprint (author’s final draft)

  • A computer experiment to simulate the dynamic behaviour of electric vehicles driven by switched reluctance motors

     Riba Ruiz, Jordi Roger; Garcia Espinosa, Antonio; Romeral Martinez, Jose Luis
    International journal of electrical engineering education
    Vol. 51, num. 4, p. 368-382
    DOI: 10.7227/IJEEE.0008
    Date of publication: 2014-10-16
    Journal article

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  • Multilevel direct power control-A generalized approach for grid-tied multilevel converter applications

     Rivera, Sebastian; Kouro, Samir; Wu, Bin; Alepuz Menendez, Salvador; Malinowski, Mariusz; Cortés, Patricio; Rodriguez, José
    IEEE transactions on power electronics
    Vol. 29, num. 10, p. 5592-5604
    DOI: 10.1109/TPEL.2013.2294711
    Date of publication: 2014-10-01
    Journal article

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    This paper presents a generalized multilevel direct power control (ML-DPC) scheme for grid-connected multilevel power converters. The proposed method extends the original DPC operating principle by considering only the closest subset of two-level voltage vectors to the present switching state. The implementation of this principle requires the power derivatives for feedback, which can present numerical problems when applied experimentally, mainly due to high measurement noise sensitivity. Therefore, a derivative estimator is proposed based on the converter-grid model in the synchronous reference frame. In addition, a virtual flux observer is developed to achieve synchronization and improve robustness in the presence of grid voltage harmonics. The proposed method is applicable to any multilevel converter topology of any number of levels. In this paper, simulations and experimental results are presented for a seven-level cascaded H-bridge converter.

  • Performance evaluation of three-phase grid-connected photovoltaic inverters using electrolytic or polypropylene film capacitors

     Karanayil, Baburaj; Agelidis, Vassilios; Pou Felix, Josep
    IEEE Transactions on Sustainable Energy
    Vol. 5, num. 4, p. 1297-1306
    DOI: 10.1109/TSTE.2014.2347967
    Date of publication: 2014-10-01
    Journal article

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    In grid-connected photovoltaic (PV) power stations, improving the life expectancy and long-term reliability of three-phase PV inverters is urgently needed to match the significantly higher lifetime of the PV modules. A key contribution toward such improvement is replacing the conventional electrolytic film capacitors by metallized polypropylene film ones. This paper presents a detailed evaluation of a conventional three-phase grid-connected PV inverter performance when replacing the electrolytic capacitor with a minimum value of metallized polypropylene film capacitor. Although the minimum dc bus capacitance leads to higher voltage ripples, such ripples were found to be within acceptable limits to operate the inverter satisfactorily. Simulation and experimental results are presented for a 5-kW grid-connected inverter prototype with a nominal dc voltage of 457 V to confirm the theoretical considerations.

  • Switched reluctance machines control with a minimized sampling frequency

     Rain, Xavier; Hilairet, Mickaël; Arias Pujol, Antoni
    Energy conversion and management
    Vol. 86, p. 701-708
    DOI: 10.1016/j.enconman.2014.05.056
    Date of publication: 2014-10-01
    Journal article

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    This paper is focused on reducing the Switched Reluctance Machines (SRMs) control sampling frequency in order to save processor real time resources, while keeping the stability and also the performance, in terms of average torque and torque ripple. Reducing the CPU cost either by implementing the control algorithm in a less performing CPU or more importantly reducing the percentage of the CPU demand is an attractive goal, especially for the electrical vehicle industry from where the SRM used in this research has been designed for. Once low sampling periods are applied in the current loop, a strong degradation in the averaged torque and torque ripple arises. Such problem degenerates with the speed, becoming unbearable at high speeds and eventually making the control unstable. In this paper two solutions are proposed. The first one, which is just software feasible, consists on anticipating the voltage supply in order to tackle the noncoincident calculated turn on and off angles and the actual sampling instants. The second solution, which must be implemented at a very low hardware level, uses a basic function to allow the process to emulate continuous control and therefore independent of the sampling instants. Finally, experimental results on a 8/6 SRM illustrate the validity of the novel strategies in terms of average torque performance and torque ripple minimization. (C) 2014 Elsevier Ltd. All rights reserved.

  • Capacitorless DC-DC converter

     Martínez García, Herminio; Grau Saldes, Antoni
    IEEE International Conference on Emerging Technologies and Factory Automation
    p. 1-6
    Presentation's date: 2014-09-19
    Presentation of work at congresses

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  • Versatility of power gyrator structures for energy processing in photovoltaic solar systems

     Martínez García, Herminio; Grau Saldes, Antoni
    IEEE International Conference on Emerging Technologies and Factory Automation
    p. 1-8
    Presentation's date: 2014-09-18
    Presentation of work at congresses

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  • Using constant switching frequency control in linear-assisted DC-DC switching converters

     Martínez García, Herminio; Grau Saldes, Antoni
    IEEE International Conference on Emerging Technologies and Factory Automation
    p. 1-6
    Presentation's date: 2014-09-18
    Presentation of work at congresses

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  • The Growing state of distributed generation and microgrids in the Ibero-American region: a view from the RIGMEI network

     Castilla Fernandez, Miguel; Gomes, Mario; Mercado, Pedro; Moreira, Carlos; Negroni Vera, Juan José; Sosa, Jorge; Zambroni de Sousa, Antonio Carlos
    IEEE PES Transmission & Distribution Conference and Exposition
    p. 1-6
    Presentation's date: 2014-09-11
    Presentation of work at congresses

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    The Ibero-American Network of Distributed Generation and Intelligent Electrical Microgrids is a thematic network of the CYTED programme that performs cooperation activities between leading companies and research groups of the Ibero-American countries in the renewable energy area. This paper presents the results and conclusions of a study carried out recently by the network, which focused on the state of penetration of the distributed generation and the electrical microgrids in the Ibero-American countries that collaborate with the network. A list of these countries, together with the contact details of the main researchers, can be found in Apendix I.

  • E-01238

     Bordonau Farrerons, Jose
    Competitive project

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  • Voltage-balancing method using phase-shifted PWM for the flying capacitor multilevel converter

     Ghias, Amer M.Y.M; Pou Felix, Josep; Ciobotaru, Mihai; Agelidis, Vassilios
    IEEE transactions on power electronics
    Vol. 29, num. 9, p. 4521-4531
    DOI: 10.1109/TPEL.2013.2285387
    Date of publication: 2014-09
    Journal article

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    Multilevel flying capacitor (FC) converters provide natural capacitor voltage balance under phase-shifted pulse width modulation (PS-PWM). However, natural balancing may not be robust enough to maintain the voltages at the reference values, especially under certain transient conditions. Furthermore, natural balancing dynamics depend on the load and it may be very slow in some practical applications. Therefore, a more robust balancing mechanism of maintaining the FC voltages at the desired values is required. This paper proposes a new closed-loop voltage-balancing method for the multilevel FC converters using PS-PWM. The proposed method balances the voltages of the FCs by modifying the duty cycle of each switch of the FC converter using a proportional controller. The crossed effect between FC currents and duty cycles is considered and is used for optimal FC voltage balancing. Simulation and experimental results verify that the proposed voltage-balancing method is very robust to different operating conditions, such as load transients, linear/nonlinear and unbalanced loads

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    The use of power DC-DC converters and gyrators structures for energy processing in photovotaic solar facilities  Open access

     Martínez García, Herminio
    International Symposium on Energy Challenges & Mechanics
    p. 1-5
    Presentation's date: 2014-08-21
    Presentation of work at congresses

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    This article provides a classification of high efficiency switching power-gyrator structures and their use as cells for energy processing in photovoltaic solar facilities. Having into account the properties of these topologies presented in the article, their inclusion in solar facilities allows increasing the performance of the whole installation. Thus, the design, simulation and implementation of a G-type power gyrator are carried out throughout the text. In addition, in order to obtain the maximum power from the photovoltaic solar panel, a maximum power point tracking (MPPT) is mandatory in the energy processing path. Therefore, the practical implementation carried out includes a control loop of the power gyrator in order to track the aforementioned maximum power point of the photovoltaic solar panel.

  • Comparative cost evaluation of heating oil and small-scale wood chips produced from Euro-Mediterranean forests

     Esteban Dalmau, Bernat; Riba Ruiz, Jordi Roger; Baquero Armans, Grau; Rius Carrasco, Antoni
    Renewable energy
    Vol. 74, p. 568-575
    DOI: 10.1016/j.renene.2014.08.038
    Date of publication: 2014-08-18
    Journal article

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  • Power gyrator structures: Versatile cells for energy processing in photovoltaic solar facilities

     Martínez García, Herminio
    IEEE International Midwest Symposium on Circuits and Systems
    p. 447-450
    DOI: 10.1109/MWSCAS.2014.6908448
    Presentation's date: 2014-08-03
    Presentation of work at congresses

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    This paper provides a classification of high efficiency switching power-gyrator structures and their use as cells for energy processing in photovoltaic solar facilities. Having into account the properties of these topologies presented in the article, their inclusion in solar facilities allows increasing the performance of the whole installation. Thus, the design, simulation and implementation of a G-type power gyrator are carried out throughout the text. In addition, in order to obtain the maximum power from the photovoltaic solar panel, a maximum power point tracking (MPPT) is mandatory in the energy processing path. Therefore, the practical implementation carried out includes a control loop of the power gyrator in order to track the aforementioned maximum power point of the photovoltaic solar panel.

  • Design of a linear-assisted DC-DC switching regulator with constant switching frequency

     Martínez García, Herminio
    IEEE International Midwest Symposium on Circuits and Systems
    p. 455-458
    DOI: 10.1109/MWSCAS.2014.6908450
    Presentation's date: 2014-08-03
    Presentation of work at congresses

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    This article shows the proposal of a linear-assisted converter or linear-&-switching hybrid converter with a constant switching frequency. The control loop of the system is based on the current-mode technique. The main disadvantage of a converter with current-mode control is the inherent instability of the loop when switch duty ratios are greater than 0.5. In order to make stable the proposed linear-assisted converter, the article shows the technique based on a slope compensation.

  • Observation of chaotic behavior in automatic tuning loops for continuous-time filters

     Martínez García, Herminio; Cosp Vilella, Jordi; Manzanares Brotons, Manuel
    IEEE International Midwest Symposium on Circuits and Systems
    p. 742-745
    DOI: 10.1109/MWSCAS.2013.6674756
    Presentation's date: 2014-08
    Presentation of work at congresses

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    he appropriate linear dynamic modeling of continuous-time filters (CTFs) with automatic tuning loops should be obtained to assure stability in case an improved design of the loop controllers is to be carried out. With this aim, starting from a general and systematic analysis in order to obtain an equivalent small-signal linearized incremental model, from which transfer functions between output variables and control voltages are derived, the subsequent design of compensated loops with enhanced stability and dynamic performance is required. This systematic procedure allows obtaining improved controllers for the two involved control loops. However, CTFs with automatic tuning loops are nonlinear feedback systems with potential instability. What is more, nonlinear phenomena, which cannot be predicted by a design-oriented small signal modeling approach, are observed in this kind of tuning systems. The purpose of this work is to highlight that when control parameters are varied, the system could present different kinds of dynamical nonlinear phenomena such as bifurcations and chaotic behavior, which cannot be predicted by the small signal design-oriented model.

  • Genetic algorithm-based output power optimisation of fault tolerant five-phase brushless direct current drives applicable for electrical and hybrid electrical vehicles

     Salehi Arashloo Arashloo, Ramin; Romeral Martinez, Jose Luis; Salehifar, Mehdi; Moreno Eguilaz, Juan Manuel
    IET electric power applications
    Vol. 8, num. 7, p. 267-277
    DOI: 10.1049/iet-epa.2013.0247
    Date of publication: 2014-08-01
    Journal article

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    This study presents a method to improve the output power of five-phase brushless direct current (BLDC) motors under different faulty conditions. Different machine connections are considered while having open-circuit fault in one and two stator phases, and both fundamental and third harmonic component of stator currents are controlled to improve the amplitude and quality of generated torque under faulty conditions. Rated root-mean-square value of stator phase currents is considered as the main limiting factor of generated electrical torque. Genetic algorithm is used in the optimisation procedure of stator reference currents to gain more output power under the fault. Automotive applications are kept in mind, and to verify the theoretical developments, experimental tests are conducted on a five-phase BLDC motor with in-wheel outer-rotor configuration.

  • Characterization and modeling of the conducted emission of integrated circuits up to 3 GHz

     Berbel Artal, Nestor; Fernández García, Raúl; Gil Galí, Ignacio
    IEEE transactions on electromagnetic compatibility
    Vol. 56, num. 4, p. 878-884
    DOI: 10.1109/TEMC.2013.2294256
    Date of publication: 2014-08-01
    Journal article

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    In this paper, an electrical model in order to predict the electromagnetic compatibility (EMC) conducted emission of integrated circuits (ICs) up to 3 GHz is presented. The electrical model predicts the behavior of the propagation paths of electromagnetic conducted emissions at high frequency by including all distributed effects and capacitive and inductive couplings. The proposed model has been compared with the standard IC emission model (ICEM-CE) to predict the EMC of a clock generator by means of the feature selective validation (FSV) method. The results show that the proposed model can expand the frequency range up to 3 GHz with a high degree of accuracy. Moreover, an alternative approach to model the electromagnetic noise that is based on the analysis of its spectral components is proposed.

  • Cooperative signal amplification for molecular communication in nanonetworks

     Abadal Cavalle, Sergi; Llatser Marti, Ignacio; Alarcon Cot, Eduardo Jose; Cabellos Aparicio, Alberto
    Wireless networks
    Vol. 20, num. 6, p. 1611-1626
    DOI: 10.1007/s11276-014-0696-z
    Date of publication: 2014-08-01
    Journal article

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    Nanotechnology is enabling the development of devices in a scale ranging from a few to hundreds of nanometers. Communication between these devices greatly expands the possible applications, increasing the complexity and range of operation of the system. In particular, the resulting nanocommunication networks (or nanonetworks) show great potential for applications in the biomedical field, in which diffusion-based molecular communication is regarded as a promising alternative to EM-based solutions due to the bio-stability and energy-related requirements of this scenario. However, molecular signals suffer a significant amount of attenuation as they propagate through the medium, thus limiting the transmission range. In this paper, a signal amplification scheme for molecular communication nanonetworks is presented wherein a group of emitters jointly transmits a given signal after achieving synchronization. This is achieved by means of quorum sensing (QS), a method used by bacteria to both sense their population and coordinate their actions. By using the proposed methodology, the transmission range is extended proportionally to the number of synchronized emitters. An analytical model of QS is provided and validated through simulation. This model is the main contribution of this work and accounts for the activation threshold (which will eventually determine the resulting amplification level) and the delay of the synchronization process.

  • On Performance Advances of Flying Capacitor Multilevel Converter Topologies

     Amer Mohammad Yusuf Mohammad Ghias
    The University of New South Wales
    Theses

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    The main focus of this thesis is to develop advanced modulation and voltage balancing methods for multilevel converter topologies, able to achieve stiff capacitor voltage regulation and reduce switching power losses of the converters. The study is focused on multilevel converter topologies based on flying capacitors (FCs), such as the multilevel flying capacitor converter (FCC) and the stacked multicell converter. Two modulation strategies are investigated; phase-shifted PWM and phase-disposition PWM, and improved voltage balancing methods have been developed and incorporated to these modulation techniques. The analysis of the converter is conducted in terms of switching frequency reduction, power losses, total harmonic distortion, and capacitor voltage ripples. This thesis also addresses the initial charging of FCs in grid-connected applications. A novel method for precharging the capacitors in the multilevel FCC is presented. The method can charge the capacitors in a controlled way besides producing low voltage and current stress to the power devices and the passive components. The method is simple and can be implemented and can be applied to FCCs with any number of levels. All the methods proposed in this thesis have been tested by simulation and experimental tests.

  • Fault Diagnosis and Fault Tolerant Control of Multiphase Voltage Source Converters For Application in Traction Drives  Open access

     Salehifar, Mehdi
    Department of Electronic Engineering, Universitat Politècnica de Catalunya
    Theses

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    Hay una creciente demanda de vehículos con menor impacto ambiental y una mayoreficiencia de combustible. Para cumplir estos requisitos, la electrificación del transporte se ha introducido en la academia y la industria en los últimos años. Vehículos eléctricos y vehículos eléctricos híbridos son dos ejemplos prácticos en los sistemas de transporte.El tren de potencia típico en los vehículos eléctricos se compone de tres partes principales, incluyendo la fuente de energía, la electrónica de potencia y un motor eléctrico. En cuanto a la máquina, de imán permanente motores son la opción dominante para vehículos híbridos ligeros en la industria debido a su mayor eficiencia y densidad de potencia. Con el fin de operar el tren de potencia, la máquina eléctrica se puede suministrar y controlado por un inversor de fuente de tensión. El convertidor se somete a diversos tipos de fallos. Según las estadísticas, 38 % de las fallas en un motor se deben al convertidor de potencia.Por otro lado, el tren de potencia eléctrica debe cumplir con un alto nivel de fiabilidad.Máquinas multifase PM pueden cumplir con los requisitos de fiabilidad debido a suscaracterísticas de tolerancia a fallos. La máquina puede seguir siendo operativo con fallas en múltiples fases. En consecuencia, para realizar una unidad de motor de alta disponibilidad de múltiples fases, tres conceptos principales deben desarrollarse incluyendo la detección de fallos, el aislamiento de fallas y control tolerante a fallos. Por tanto, esta tesis doctoral se centra en la FD y control tolerante a fallos de un VSI multifase.Para lograr este objetivo la investigación, los productos alimenticios y bebidas y métodos de control que se presentan del convertidor de potencia se investigan a fondo a través de revisión de la literatura. Después de eso, se estudió la condición operativa del convertidor de múltiples el suministro de la máquina eléctrica.En cuanto a los métodos de FD en múltiples fases, tres nuevos algoritmos se presentan en esta tesis. Estos métodos FD propuestas también están integrados en los nuevos algoritmos de control con tolerancia a fallos. En el primer paso, se propone un método FD modelo novela basada detectar fallas múltiples del interruptor abierto. Este método FD está incluido en el algoritmo de control adaptativo desarrollado proporcional resonante del convertidor de potencia.En el segundo paso, se proponen dos métodos FD señal basada. Se discute el control tolerante a fallos del convertidor de potencia con el controlador PI convencional. Además, la teoría de la SMC se desarrolla. En el último paso, el control conjunto finito modelo de control predictivo del motor de cinco fases sin escobillas de corriente continua se discutió por primera vez en estatesis. Un método FD sencilla se deriva de las señales de control. Las entradas a todos los métodos desarrollados son las corrientes de cinco de fase del motor.La teoría de cada método se explica y se compara con los métodos disponibles. Paravalidar la teoría desarrollada en cada parte, FD algoritmo está incorporado en el algoritmo de control tolerante a fallos. Los resultados experimentales se llevan a cabo en una unidad de motor BLDC de cinco fases. El motor eléctrico usado en los resultados experimentales tiene una estructura de rotor exterior en las cuatro ruedas. Este motor es adecuado para los vehículos eléctricos. Al final de cada parte, se presentan los puntos notables y conclusiones.

    There is an increasing demand for vehicles with less environmental impact and higher fuel efficiency. To meet these requirements, the transportation electrification has been introduced in both academia and industry during last years. Electric vehicle (EV) and hybrid Electric vehicle (HEV) are two practical examples in transportation systems. The typical power train in the EVs consists of three main parts including energy source, power electronics and an electrical motor. Regarding the machine, permanent magnet (PM) motors are the dominant choice for light duty hybrid vehicles in industry due to their higher efficiency and power density. In order to operate the power train, the electrical machine can be supplied and controlled by a voltage source inverter (VSI). The converter is subjected to various fault types. According to the statistics, 38% of faults in a motor drive are due to the power converter. On the other side, the electrical power train should meet a high level of reliability. Multiphase PM machines can meet the reliability requirements due to their fault-tolerant characteristics. The machine can still be operational with faults in multiple phases. Consequently, to realize a multiphase fault-tolerant motor drive, three main concepts should be developed including fault detection (FD), fault isolation and fault-tolerant control. This PhD thesis is therefore focused on FD and fault-tolerant control of a multiphase VSI. To achieve this research goal, the presented FD and control methods of the power converter are thoroughly investigated through literature review. Following that, the operational condition of the multiphase converter supplying the electrical machine is studied. Regarding FD methods in multiphase, three new algorithms are presented in this thesis. These proposed FD methods are also embedded in new fault-tolerant control algorithms. At the first step, a novel model based FD method is proposed to detect multiple open switch faults. This FD method is included in the developed adaptive proportional resonant control algorithm of the power converter. At the second step, two signal based FD methods are proposed. Fault-tolerant control of the power converter with the conventional PI controller is discussed. Furthermore, the theory of SMC is developed. At the last step, finite control set (FCS) model predictive control (MPC) of the five-phase brushless direct current (BLDC) motor is discussed for the first time in this thesis. A simple FD method is derived from the control signals. Inputs to all developed methods are the five-phase currents of the motor. The theory of each method is explained and compared with available methods. To validate the developed theory at each part, FD algorithm is embedded in the fault-tolerant control algorithm. Experimental results are conducted on a five-phase BLDC motor drive. The electrical motor used in the experimental results has an in-wheel outer rotor structure. This motor is suitable for electric vehicles. At the end of each part, the remarkable points and conclusions are presented

    Hay una creciente demanda de vehículos con menor impacto ambiental y una mayor eficiencia de combustible. Para cumplir estos requisitos, la electrificación del transporte se ha introducido en la academia y la industria en los últimos años. Vehículos eléctricos y vehículos eléctricos híbridos son dos ejemplos prácticos en los sistemas de transporte. El tren de potencia típico en los vehículos eléctricos se compone de tres partes principales, incluyendo la fuente de energía, la electrónica de potencia y un motor eléctrico. En cuanto a la máquina, de imán permanente motores son la opción dominante para vehículos híbridos ligeros en la industria debido a su mayor eficiencia y densidad de potencia. Con el fin de operar el tren de potencia, la máquina eléctrica se puede suministrar y controlado por un inversor de fuente de tensión. El convertidor se somete a diversos tipos de fallos. Según las estadísticas, 38 % de las fallas en un motor se deben al convertidor de potencia. Por otro lado, el tren de potencia eléctrica debe cumplir con un alto nivel de fiabilidad. Máquinas multifase PM pueden cumplir con los requisitos de fiabilidad debido a sus características de tolerancia a fallos. La máquina puede seguir siendo operativo con fallas en múltiples fases. En consecuencia, para realizar una unidad de motor de alta disponibilidad de múltiples fases, tres conceptos principales deben desarrollarse incluyendo la detección de fallos, el aislamiento de fallas y control tolerante a fallos. Por tanto, esta tesis doctoral se centra en la FD y control tolerante a fallos de un VSI multifase. Para lograr este objetivo la investigación, los productos alimenticios y bebidas y métodos de control que se presentan del convertidor de potencia se investigan a fondo a través de revisión de la literatura. Después de eso, se estudió la condición operativa del convertidor de múltiples el suministro de la máquina eléctrica. En cuanto a los métodos de FD en múltiples fases, tres nuevos algoritmos se presentan en esta tesis. Estos métodos FD propuestas también están integrados en los nuevos algoritmos de control con tolerancia a fallos. En el primer paso, se propone un método FD modelo novela basada detectar fallas múltiples del interruptor abierto. Este método FD está incluido en el algoritmo de control adaptativo desarrollado proporcional resonante del convertidor de potencia. En el segundo paso, se proponen dos métodos FD señal basada. Se discute el control tolerante a fallos del convertidor de potencia con el controlador PI convencional. Además, la teoría de la SMC se desarrolla. En el último paso, el control conjunto finito modelo de control predictivo del motor de cinco fases sin escobillas de corriente continua se discutió por primera vez en esta tesis. Un método FD sencilla se deriva de las señales de control. Las entradas a todos los métodos desarrollados son las corrientes de cinco de fase del motor. La teoría de cada método se explica y se compara con los métodos disponibles. Para validar la teoría desarrollada en cada parte, FD algoritmo está incorporado en el algoritmo de control tolerante a fallos. Los resultados experimentales se llevan a cabo en una unidad de motor BLDC de cinco fases. El motor eléctrico usado en los resultados experimentales tiene una estructura de rotor exterior en las cuatro ruedas. Este motor es adecuado para los vehículos eléctricos. Al final de cada parte, se presentan los puntos notables y conclusiones

  • Fault Tolerant Vector Control of Five-Phase Permanent Magnet Motors

     Salehi Arashloo Arashloo, Ramin
    Department of Electronic Engineering, Universitat Politècnica de Catalunya
    Theses

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    Equipado con las estrategias de control adecuadas, los motores de imanes permanentes (PM motors) son de los tipos más flexibles de actuadores en muchas aplicaciones industriales. Entre diferentes tipos de estas máquinas, las maquinas BLDC con cinco fases son muy interesantes para aplicaciones tolerantes a fallos.En estas máquinas, la mejora del par puede llevarse a cabo mediante la optimización del diseño de la maquina o mediante la mejora de métodos de control.En esta tesis, se proponen nuevos controladores de corriente para mejorar la calidad del par generado en las condiciones normales de un BLDC pentafasico.Controladores propuestos se basan en una combinación de controladores predictivos (Model Predictie Control), y estimadores avanzados como 'Extended Kalman Filter'.Estos controladores serán una base para funcionamiento del motor bajo condiciones defectuosas.En este estudio, también se ha considerado el funcionamiento de máquinas BLDC pentafasicas en condiciones defectuosas. Para mejorar el par generado bajo condiciones defectuosas, la amplitud y ángulo del primer y tercer harmónicos de corrientes se han optimizado para las fases sanas. En condiciones defectuosas, las consignas de corriente apropiadas tienen dinámicas oscilantes y periódicos.Como resultado, en estas condiciones, los controladores implementados deben ser robustos y rápidos. En este estudio, también se proponen controladores predictivos para las condiciones defectuosas de la maquina BLDC de cinco fases.Las maquinas BLDC pentafasicas son muy interesantes para aplicaciones de automoción como vehículos eléctricos y aviones más eléctricos. En todas estas aplicaciones, la eficiencia de la maquina es muy importante. En esta tesis, la eficiencia de una maquina BLDC pentafasica se evalúa para condiciones normales, y también para condiciones defectuosas.Para verificar las teorías desarrolladas, siempre evaluaciones experimentales se llevan a cabo. Estas teorías incluyen métodos propuestos para controlar las corrientes, y la eficiencia simulada de la maquina bajo diferentes condiciones de operación.

  • De la teoría a la práctica: cinco años después de la integración de la competencia genérica de sostenibilidad en el Grado en Ingeniería Informática  Open access

     Garcia Almiñana, Jordi; Sanchez Carracedo, Fermin; Lopez Alvarez, David; Vidal Lopez, Eva Maria; Cabre Garcia, Jose Maria; García García, Helena; Alier Forment, Marc
    Jornadas de Enseñanza Universitaria de la Informática
    p. 253-260
    Presentation's date: 2014-07-09
    Presentation of work at congresses

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    La sostenibilidad es una de las competencias trans- versales básicas que todo ingeniero debería adquirir durante su formación. De hecho, seguir desarrollando ciencia y tecnología de espaldas a la sostenibilidad provocaría en poco tiempo un colapso de nuestro planeta. La puesta en marcha del Espacio Europeo de Educación Superior (EEES) ha propiciado una opor- tunidad única para replantearse diferentes aspectos educativos, entre los cuales destaca la inclusión de esta competencia en los planes de estudio. Existe literatura abundante sobre estrategias y pro- puestas teóricas para incluir esta competencia en las ingenierías. Sin embargo, pocos trabajos han sido llevados a cabo desde una perspectiva más práctica. La Facultat de Informàtica de Barcelona (FIB) posee amplia experiencia en el diseño de titulaciones adap- tadas al EEES y ha integrado la sostenibilidad en su plan de estudios de Grado en Ingeniería Informática. En este trabajo se revisa el proceso de diseño del plan de estudios de Grado en Ingeniería Informática de la FIB, aprobado en el año 2009, y se analiza la experiencia de integración de la sostenibilidad tras cinco años de funcionamiento del grado. Se comentan los mecanismos de organización y coordinación entre las asignaturas implicadas y, finalmente, se extraen las lecciones aprendidas.

    La sostenibilidad es una de las competencias transversales básicas que todo ingeniero debería adquirir durante su formación. De hecho, seguir desarrollando ciencia y tecnología de espaldas a la sostenibilidad provocaría en poco tiempo un colapso de nuestro planeta. La puesta en marcha del Espacio Europeo de Educación Superior (EEES) ha propiciado una oportunidad única para replantearse diferentes aspectos educativos, entre los cuales destaca la inclusión de esta competencia en los planes de estudio. Existe literatura abundante sobre estrategias y propuestas teóricas para incluir esta competencia en las ingenierías. Sin embargo, pocos trabajos han sido llevados a cabo desde una perspectiva más práctica. La Facultat de Informàtica de Barcelona (FIB) posee amplia experiencia en el diseño de titulaciones adaptadas al EEES y ha integrado la sostenibilidad en su plan de estudios de Grado en Ingeniería Informática. En este trabajo se revisa el proceso de diseño del plan de estudios de Grado en Ingeniería Informática de la FIB, aprobado en el año 2009, y se analiza la experiencia de integración de la sostenibilidad tras cinco años de funcionamiento del grado. Se comentan los mecanismos de organización y coordinación entre las asignaturas implicadas y, finalmente, se extraen las lecciones aprendidas.

    SUMMARY -- Sustainability is one of the basic professional skills that every engineer should incorporate during their training. In fact, developing science and technology without sustainability criteria would collapse our planet. The launching of the European Higher Education Area (EHEA) has provided a unique opportunity to rethink different educational aspects, including the integration of this skill into the curriculum. Abundant literature exists on strategies and theoretical proposals to include this skill into engineering. However, few studies have been done from a more practical perspective. The Barcelona School of Informatics (FIB) has wide experience in the design of degrees according to the EHEA, and has integrated sustainability into the Informatics Engineering degree. This paper reviews the process of the design of the FIB’s Informatics Engineering degree curriculum, approved in 2009, and analyses the experience of sustainability integration after five years. The organizational and coordination mechanisms between the subjects are discussed, and finally the lessons learnt are extracted.

  • Optimization of WPT efficiency using a conjugate load in non-impedance matched systems.

     Chabalko, Matthew; Alarcon Cot, Eduardo Jose; Bou Balust, Elisenda; Ricketts, David S.
    IEEE International Symposium on Antennas and Propagation
    p. 645-646
    DOI: 10.1109/APS.2014.6904653
    Presentation's date: 2014-07-06
    Presentation of work at congresses

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    Maximum power transfer and maximum efficiency are two important design constraints in wireless power transfer applications. Several works have investigated the proper load and impedance match conditions to optimize either efficiency or power transfer. In this paper we show that the optimal load for maximum power transfer and maximum efficiency is the same (a conjugate matched load) when the source resistance is zero. This is important, as many WPT systems have a relatively low, unknown source impedance. Since the optimal load for both efficiency and power is the same as the source impedance approaches zero, the designer can use a bi-conjugate load for a near optimal design for both maximum power and efficiency. As the source impedance becomes significant, the bi-conjugate matched system provides higher power, but at the expense of lower efficiency. Maximum efficiency is achieved with a non-bi-conjugate load, when the source impedance is non-negligible.

  • La experiencia del equipo ETSEIB-ELISAVA en la Barcelona Smart Moto Challenge: Un proyecto Learning-by-doing de diseño e ingeniería

     Moreno Eguilaz, Juan Manuel; Garcia Espinosa, Antonio; Riba Ruiz, Jordi Roger; Ortega Redondo, Juan Antonio; Romeral Martinez, Jose Luis; Hernandez Chiva, Emilio
    Congrés Internacional de Docència Universitària i Innovació
    Presentation's date: 2014-07-02
    Presentation of work at congresses

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  • Performance improvement of a prefiltered synchronous-reference-frame PLL by using a PID-type loop filter

     Golestan, Saeed; Monfared, Mohammad; Freijedo Fernández, Francisco Daniel; Guerrero Zapata, Josep Maria
    IEEE transactions on industrial electronics
    Vol. 61, num. 7, p. 3469-3479
    DOI: 10.1109/TIE.2013.2282607
    Date of publication: 2014-07-01
    Journal article

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    Control Parameters design of a three-phase synchronous reference frame phase locked loop (SRF-PLL) with a prefiltering stage (acting as the sequence separator) is not a trivial task. The conventional way to deal with this problem is to neglect the interaction between the SRF-PLL and prefiltering stage, and treat them as two separate systems. This approach, although very simple, is not optimum as the prefiltering stage and the SRF-PLL may have comparable dynamics. The aim of this paper is to develop a systematic and efficient approach to design the control parameters of the SRF-PLL with prefiltering stage. To this end, the paper first optimizes the performance of the prefiltering stage in detection of the sequence components. The paper then proceeds to reduce the interaction between the prefiltering stage and SRF-PLL, which is achieved by employing a derivative-filtered proportional-integral-derivative controller as the loop filter (instead of the commonly adopted proportional-integral controller) and arranging a pole-zero cancellation. The suggested method is simple and efficient, and is applicable to the joint operation of different sequence separation techniques and the SRF-PLL. The effectiveness of the suggested design approach is confirmed through extensive experimental results.

  • Global MPPT scheme for photovoltaic string inverters based on restricted voltage window search algorithm

     Boztepe, Mutlu; Guinjoan Gispert, Francisco; Velasco Quesada, Guillermo; Silvestre Berges, Santiago; Chouder, Aissa; Karatepe, Engin
    IEEE transactions on industrial electronics
    Vol. 61, num. 7, p. 3302-3312
    DOI: 10.1109/TIE.2013.2281163
    Date of publication: 2014-07-01
    Journal article

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    String inverter photovoltaic (PV) systems with bypass diodes require improved global maximum power point tracking (GMPPT) algorithms to effectively reach the absolute maximum power operating point. Several GMPPT algorithms have been proposed to deal with this problem, but most of them require scanning wide voltage ranges of the PV array from nearly zero voltage to open-circuit voltage that increases the scanning time and, in turn, causes energy loss. This paper presents a novel GMPPT method which significantly restricts the voltage window search range and tracks the global power peak rapidly in all shading conditions. Simulation tests and experimental comparisons with another GMPPT algorithm are presented to highlight the features of the presented approach.

  • Simulation of multi-radio multi-channel 802.11-based mesh networks in ns-3

     Amiri-Nezhad, Maryam; Guerrero Zapata, Josep Maria; Bellalta Jimenez, Boris; Cerdà Alabern, Llorenç
    Eurasip journal on wireless communication and networking
    num. 118, p. 1-19
    DOI: 10.1186/1687-1499-2014-118
    Date of publication: 2014-07
    Journal article

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    In the context of wireless network simulation, many simulators are capable of evaluating the performance of single-channel network protocols, but they need many modifications to be able to simulate multi-radio multi-channel networks. We address the problem of simulating channel assignment protocols for multi-radio wireless mesh networks in ns-3 simulator, providing the essential steps needed to simulate a channel assignment protocol. In addition, we explain the details of simulating the Semi-dynamic Interference aware Channel Assignment (SICA) protocol as an example. We use SICA as a reference to address the challenges of validating and verifying the simulation model. To validate the channel assignment model in SICA, we use mathematical validation based on Markov chains. Furthermore, we propose a novel automated test module to verify the simulation process.